Replaced belt in 30 minutes. Longest time was spent trying to figure out how the belt went around the pulley and then re-removing the drum to find a dropped screw.
Superfast delivery, received in 1 day! Ordered on Sunday, shipped on Monday and received on Tuesday.

I received the replacement two days after ordering, with standard shipping! Replacing was easy, and the new blower works fine, so quiet now compared to the failing one. However the dryer (24 years old) appears to also have a balky gas valve, so I will be replacing the valve coils. I am happy to recommend Appliance Parts Pro.